Sign up to receive free email alerts when patent applications with chosen keywords are publishedSIGN UP

Abstract:

In a multi-tip stylus pen for a touch-screen device includes an elongated
body member which may be capped with a hollow cap member. The hollow cap
member has a first stylus tip member disposed at one of the cap ends
without an opening. The first stylus tip member includes a first rounded
tip of a material and shape suitable for contact with the touch-screen.
The elongated body member has a second stylus tip member disposed at a
first end. The second stylus tip member comprises a second stylus tip
having a second rounded tip of a material and shape suitable for contact
with the touch-screen. A third stylus tip member may be disposed at a
second end of the body member. The third stylus tip comprises a third
rounded tip of a material and shape suitable for contact with the
touch-screen.

Claims:

1. A multi-tip stylus pen for inputting information into a computing
device through touching a touchscreen of the computing device comprising:
an elongated body member having a first end and a second end; a hollow
cap member comprising: an inner cavity with an opening at a first end of
the cap member configured to receive the second end of the body member;
and a first stylus tip member disposed at a second end of the cap member,
the first stylus tip member comprising a first stylus tip, the first
stylus tip comprising a first rounded tip of a material and a shape
suitable for contact with the touchscreen; a second stylus tip member
disposed at the first end of the body member, the second stylus tip
member comprising a second stylus tip, the second stylus tip comprising a
second rounded tip of a material and shape suitable for contact with the
touchscreen; and a third stylus tip member disposed at a second end of
the body member, the third stylus tip member comprising a third stylus
tip, the third stylus tip comprising a third rounded tip of a material
and shape suitable for contact with the touchscreen.

2. The stylus pen of claim 1, wherein the first rounded tip has a first
base width greater than a second base width of the second rounded tip.

3. The stylus pen of claim 2, wherein the first rounded tip comprises a
first hemispherical dome tip portion, the first dome tip portion having a
first diameter substantially equal to the first base width, and a first
cylindrical portion, the first cylindrical portion having the first
diameter.

4. The stylus pen of claim 2, wherein the second rounded tip has a second
base width greater than a third base width of the third rounded tip.

5. The stylus pen of claim 4, wherein the second rounded tip comprises a
second hemispherical dome tip portion, the second dome tip portion having
a second diameter substantially equal to the second base width, and a
second cylindrical portion, the second cylindrical portion having the
second diameter.

6. The stylus pen of claim 4, wherein the body member comprises an
elongated cylindrical portion having a body diameter greater than the
first base width.

7. The stylus pen of claim 4, wherein the hollow cap member is configured
to receive the first end of the body member.

8. The stylus pen of claim 1, wherein any one of the first, second, and
third stylus tips are coupled to the body member through an electrically
conductive removable link member.

9. The stylus pen of claim 1, wherein the first stylus tip has a first
diameter between 6.5 mm and 9 mm.

10. The stylus pen of claim 9, wherein the second stylus tip has a second
diameter between 5.5 mm and 6.5 mm.

11. The stylus pen of claim 10, wherein the third stylus has a third
diameter between 1.0 mm and 5.5 mm.

12. The stylus pen of claim 1, wherein at least one of the first stylus
tip, the second stylus tip, or the third stylus tip comprises a hollow
cavity enclosed therein and a cavity wall having a cavity wall thickness.

13. The stylus pen of claim 12, wherein the at least one of the first,
second, and third stylus tips comprise an elastomeric material, the
elastomeric material designed to deform in a direction parallel to an
axis of elongation of the body member towards the touch screen by an
amount proportional to an amount of force applied in the elongate
direction.

16. The stylus pen of claim 13, wherein the cavity wall thickness is
between 0.3 mm and 0.8 mm.

17. The stylus pen of claim 16, wherein the at least one of the first,
second, and third stylus tips have a resistivity between 0.01 and 1 Ohms.

18. The stylus pen of claim 1, wherein any one of the first, second, and
third rounded tips have at least one cross section having a shape chosen
from a group consisting of a circle, an oval, a triangle, rectangle, a
pentagon, a hexagon, an octagon, and a diamond.

19. The stylus pen of claim 1, wherein the body member has at least one
cross section area having a shape chosen from a group consisting of a
circle, an oval, a triangle, rectangle, a pentagon, a hexagon, an
octagon, and a diamond.

20. The stylus pen of claim 1, wherein the cap member has a length
sufficient to cover at least one third of the body member.

21. The stylus pen of claim 1, wherein the cap member further comprises
an elastic clip configured to attach the cap member to a sheet or a shirt
pocket.

22. A multi-tip stylus pen for inputting information into a computing
device through touching a touchscreen of the computing device comprising:
an elongated body member having a first end and a second end; a hollow
cap member comprising: an inner cavity with an opening at a first end of
the cap member configured to receive the second end of the body member;
and a first stylus tip member disposed at a second end of the cap member,
the first stylus tip member comprising a first stylus tip, the first
stylus tip comprising a first rounded tip of a material and shape
suitable for contact with the touchscreen; a second stylus tip member
disposed at the first end of the body member, the second stylus tip
member comprising a second stylus tip, the second stylus tip comprising a
second rounded tip of a material and shape suitable for contact with the
touchscreen; and

23. The stylus pen of claim 22, further comprising a writing member
disposed at a second end of the body member, the writing member
comprising writing tip suitable for writing on a writing surface.

24. The stylus pen of claim 23, wherein the writing tip is a ball point
tip.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent
Application No. 61/591,391, filed Jan. 27, 2012, the disclosure of which
is hereby incorporated by reference in its entirety.

FIELD

[0002] Embodiments relate to input devices for touchscreen device, more
specifically to multi-tip stylus pen for electronic devices with
touchscreens.

BACKGROUND

[0003] Touch-screens are both an output interface for displaying
information from an electronic device to the user and an input interface
for inputting information by the user into electronic devices.
Touch-screens are often intended to be used with fingers. While fingers
may provide adequate touch resolution for inputting some types of
information, they may be inadequate for other types of information. For
example, fingers may provide inadequate touch resolution when the user
wishes to input information requiring a higher degree of touch resolution
such as in intricate drawing or a signature. For such types of input
information a stylus pen having the requisite degree of touch resolution
may provide a solution. However, a stylus pen having adequate touch
resolution for one type of input information may not have adequate
resolution for another type of input information. For example, a stylus
pen having a relatively high degree of resolution for inputting hand
writing may have too high of a resolution for creating artistic brush
strokes. In addition, a stylus pen having a relatively low touch
resolution adequate for typing on large on-screen keyboard of a
relatively large touch-screen device such as a tablet computer may be
inadequate for typing on small on-screen keyboard of a relatively small
touch-screen device such as mobile phone. Under these circumstances,
carrying multiple stylus pens having multiple touch resolutions may be
cumbersome. Thus, there is a need for a stylus pen having more than one
stylus tip with multiple touch resolutions.

SUMMARY OF THE INVENTION

[0004] In one embodiment, a multi-tip stylus pen includes an elongated
body member having a first end and a second end and a hollow cap member.
The hollow cap member comprises an inner cavity with an opening at a
first end configured to receive the second end of the body member. A
first stylus tip member is disposed at a second end of the hollow cap
member. The first stylus tip member comprising a first stylus tip is
disposed at the second end of the hollow cap member. The first stylus tip
comprises a first rounded tip of a material and shape suitable for
contact with the touchscreen. The embodiment further comprises a second
stylus tip member disposed at the first end of the body member. The
second stylus tip member comprises a second stylus tip comprising a
second rounded tip of a material and shape suitable for contact with the
touch-screen. Additionally, a third stylus tip member is disposed at a
second end of the body member and comprises a third stylus tip. The third
stylus tip comprises a third rounded tip of a material and shape suitable
for contact with the touchscreen.

[0005] In another embodiment, a multi-tip stylus pen includes an elongated
body member having a first end and a second end and a hollow cap member.
The hollow cap member comprises an inner cavity with an opening at a
first end configured to receive the second end of the body member. A
first stylus tip member is disposed at a second end of the hollow cap
member. The first stylus tip member comprising a first stylus tip is
disposed at the second end of the hollow cap member. The first stylus tip
comprises a first rounded tip of a material and shape suitable for
contact with the touchscreen. The embodiment further comprises a second
stylus tip member disposed at the first end of the body member. The
second stylus tip member comprises a second stylus tip comprising a
second rounded tip of a material and shape suitable for contact with the
touchscreen.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 is a schematic view illustrating an input to the touch
screen device made in the form of a hand-drawn picture made using a
multi-tip stylus pen, according to an embodiment of the present
invention.

[0007] FIG. 2 is an elevational side view illustrating a multi-tip stylus
pen with a cap member covering a portion of the body member according to
an embodiment of the present invention, showing first and second stylus
tip members.

[0008] FIG. 3 is an elevational side view illustrating the multi-tip
stylus pen of FIG. 2 with the cap member disengaged from the body member,
showing first, second, and third stylus tip members.

[0009] FIG. 4A is a close up view of an end of the cap member of FIG. 2,
showing a first tip member according to an embodiment of the present
invention.

[0010] FIG. 4B is an end view of the cap member of FIG. 4B.

[0011] FIG. 5A is a close up view of an end of the body member of FIG. 2,
showing a second tip member according to an embodiment of the present
invention.

[0012] FIG. 5B is an end view of the body member of FIG. 5A.

[0013] FIG. 6 is a side elevational view of a multi-tip stylus pen
according to another embodiment, showing a cap removed and a writing tip
at one end of the body member.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0014] Referring to FIG. 1, a multi-tip stylus pen 10 is illustrated
alongside with a touch-screen device 2. The touch screen device 2
includes a touch screen 4. Depicted in FIG. 1 is an input drawing 6 made
using the multi-tip stylus pen 10.

[0015] While the touch-screen device 2 illustrated in FIG. 1 is a tablet
computer, electronic devices that may be used with a multi-tip stylus pen
10 include any touch screen-enabled electronic devices including game
consoles, desktop computers, laptop computers, mobile phones,
smartphones, personal digital assistants (PDAs), satellite navigation
devices, cameras, GPS units, interactive displays in automobiles or on
appliances, and similar devices.

[0016] A touchscreen 4 is a component of an electronic device that
functions both as a visual display output device as well as an input
device that allows a user to input information into the electronic
device. The touchscreen enables the user to interact directly with what
is displayed, rather than using a mouse, touchpad, or any other
intermediate "pointer" device (other than a stylus, which is optional for
most modern touchscreens). A user may input information in the form of a
simple touch or multi-touch gestures. The simple touch or multi-touch
gestures may be generated by human fingers or by a suitable touch input
device such as a stylus pen or other similar means that are able to
generate electrical signals in the electronic device in response to the
touch.

[0017] Under certain circumstances, the user may prefer a human finger or
a relatively coarse touch input device, such as a stylus tip pen having a
stylus tip with a tip size similar in dimensions to a human finger. This
may be the case for typing on a relatively large key board displayed on
the touchscreen of a relatively large device such as a tablet computer.
Similarly, making broad-stroked lines 8b such as that may be present in
the drawing 6 may be best performed with a human finger or a stylus pen
having a relatively large stylus tip. The touchscreen device may also
recognize the use of a larger stylus and react to it differently, e.g.,
treat a large stylus as an eraser in a drawing program, which smaller
stylus tips are treated as pens. Under other circumstance, the user may
prefer a touch input device such as a stylus pen having a stylus tip size
substantially smaller than a human finger. Such may be the case when
typing on a relatively small key board displayed on the touchscreen of a
relatively small device, such as a smartphone. Such may also be the case
when a user wishes to hand sign an electronic document. Similarly, making
fine lines 8a such as that may be present in the drawing 6 may be best
performed using a stylus pen having a relatively small stylus tip. It is
relatively common for people to carry multiple touch screen devices
having varying sizes of touch screens that may be best utilized with
multiple stylus tips. Carrying multiple stylus tip pens having different
tip sizes may be cumbersome. Thus, there is a need for a stylus pen
having multiple stylus tips for multiple purposes.

[0018] In FIGS. 2 and 3, a multi-tip stylus pen 10 according to a
preferred embodiment of the invention is illustrated. In particular, a
multi-tip stylus pen 10 includes an elongated body member 20 having a
first end and a second end and a hollow cap member 30. The hollow cap
member 30 comprises an inner cavity with an opening 32 at a first end
configured to receive the second end of the body member 20, and optional
also to receive the first end of the body member 20. A first stylus tip
member 50 comprising a first stylus tip 52 is disposed at a second end of
the hollow cap member 30. The first stylus tip 52 comprises a first
rounded tip of a material and shape suitable for contact with the
touchscreen. The preferred embodiment further comprises a second stylus
tip member 40 disposed at the first end of the body member 20. The second
stylus tip member 40 comprises a second stylus tip 42 comprising a second
rounded tip of a material and shape suitable for contact with the
touchscreen. Additionally, a third stylus tip member 70 is disposed at a
second end of the body member 20 and comprises a third stylus tip 72. The
third stylus tip 72 comprises a third rounded tip of a material and shape
suitable for contact with the touchscreen.

[0019] FIG. 2 illustrates the multi-tip stylus pen 10 in which the hollow
cap member 30 has received the body member 20 such that the hollow cap
member 30 covers a substantial portion of the body member 20. FIG. 3
illustrates the multi-tip stylus pen 10 in which the body member 20 and
the hollow cap member 30 are disengaged from each other and shows the
entire length of the body member 20.

[0020] In FIG. 2, the hollow cap member 30 has received the second body
end of the elongated body member 20 such that the portion of the body
member 20 inside the hollow cap member 30 is not shown. In an embodiment,
the portion of the length of the body member 20 that is enclosed inside
the hollow cap member 30 when fully inserted is approximately 20-40% of
the length of the body member 20. In another embodiment, the portion is
approximately 40-60%. In yet another embodiment, the portion is
approximately 60-80%.

[0021] While FIG. 2 shows the hollow cap member 30 having received the
second end of the elongated body member 20, other embodiments are
possible. In another embodiment, the cap member 30 may receive the first
end of the elongated body member 20. As noted, the hollow cap member 30
can be configured to fit over both the first end and the second end of
the body member 20.

[0022] Additionally, an O-ring 46 may be included between at either end
the first or the second end of the elongated body member 20. When
present, the O-ring may improve the fit between the outer surface of
first or the second end of the elongated body member 20 and the inner
surface of the hollow cap member 30 to have a more secure fit between
them. The O-ring 46 may be supported by an O-ring gasket 48.

[0023] The hollow cap member 30 comprises hollow cavity walls that
surround the body member 20 when the hollow cap member 30 has received
the body member 20. In one embodiment, the hollow cavity walls have a
thickness ranging from 0.1 to 0.5 mm. In another embodiment, the hollow
cavity walls have a thickness ranging from 0.5 to 1 mm. In yet another
embodiment, the hollow cavity walls have a thickness ranging from 1 to 2
mm.

[0024] The first stylus tip 52 comprises a first rounded tip of a shape
suitable for making contact with the touch screen 4. In the illustrated
embodiment in FIG. 2, the first rounded tip 52 comprises a first
hemispherical dome tip portion and a first cylindrical portion. The first
hemispherical dome tip portion and the first cylindrical portion have
substantially the same diameters such that the first hemispherical dome
tip portion makes a smooth transition into the first cylindrical portion
with a continuously varying radius of curvature.

[0025] FIG. 2 illustrates the second stylus tip member 40 disposed at the
first end of the body member 20. The second stylus tip 42 comprises a
first rounded tip of a shape suitable for making contact with the touch
screen. In the illustrated embodiment in FIG. 2, similar to the first
rounded tip 52, the second rounded tip 42 comprises a second
hemispherical dome tip portion and a second cylindrical portion that have
substantially the same diameters such that the second hemispherical dome
tip portion makes a smooth transition into the second cylindrical portion
with a continuously varying radius of curvature.

[0026] Referring to FIG. 3, the disengaged elongated body member 20
includes the third stylus tip member 70 disposed at the second end. The
third stylus tip 72 comprises a third rounded tip of a shape suitable for
making contact with the touch screen. In the illustrated embodiment in
FIG. 3, similar to the first and second rounded tips 52 and 42, the third
rounded tip 72 comprises a third hemispherical dome tip portion and a
third cylindrical portion that have substantially the same diameters such
that the third hemispherical dome tip portion makes a smooth transition
into the third cylindrical portion with a continuously varying radius
curvature.

[0027] While the first, second, and third rounded tips of first, second,
and third stylus tips 52, 42, and 72 in FIGS. 2 and 3 are illustrated
with circular-symmetric shapes including a hemispherical dome tip portion
and a cylindrical portion, other shapes are possible in other
embodiments. Any one of the first, second, and third rounded tips of the
first, second, and third stylus tips 52, 42, and 72 may be formed of
other suitable shapes such that the first stylus tips have
cross-sectional views in a direction perpendicular to the lengthwise
direction that are not circular symmetric. For example, any one of the
first, second, and third rounded tips may be shaped such that at least
one cross-sectional area is in the shape of an oval triangle, rectangle,
a pentagon, a hexagon, an octagon, a diamond, or any other suitable
shape.

[0028] One of the considerations in designing the rounded tips to enhance
the user experience is the elasticity of the tips. The elastic constant
of a tip relates to the amount of force perpendicular to the plane of the
touch screen 4 that may be applied to achieve a desirable input to the
touch screen. For example, in making a drawing such as the drawing 6 in
FIG. 1, a tip having a relatively high elastic constant entails a
correspondingly higher amount of vertical force to generate the same area
of contact between the stylus tip and the touch screen compared to a tip
having a relatively low elastic constant. In some embodiments, the
rounded tips are designed to have a correspondence between the amount of
vertical force and the resulting lines that resemble, for example, an
actual correspondence that a user expects from physical artistic tools
such as brushes and pastels. In other embodiments, the elastic constant
of the rounded tips may be optimized to provide maximum protection to the
touch screen. The elasticity depends on many factors, including the
elasticity of the tip material, the shape of the tip, whether the tips
are solid or hollow, and whether there are other elasticity enhancing
features embedded within the tips (e.g., a spring).

[0029] A related consideration in designing the rounded tips is the
friction coefficient between the tip surface and the touch screen
surface. The friction coefficient relates to the amount force parallel to
the plane of the touch screen 4 that may be applied to achieve a
desirable input to the touch screen. In some embodiments, the rounded
tips are designed to have lowest friction coefficient practically
achievable to render a freely gliding feel to the user. In other
embodiments, the rounded tips are designed to have a higher friction
coefficient. Again referring the example of the drawing 6 in FIG. 1, the
rounded tips may be designed to have a correspondence between the amount
of lateral force and the resulting lines that resemble, for example, an
actual correspondence that a user expects from physical artistic tools
such as brushes and pastels to enhance the user experience. The friction
coefficient depends on many factors, including the material type of the
tip and the shape of the tip.

[0030] As the amount of lateral force that may be applied to generate an
input on a touch screen also depends on the area of contact between the
stylus tip and the touch screen, an optimum user experience may be
obtained when the elastic coefficient and the friction coefficient are
optimized as a whole.

[0031] In this connection, in an embodiment of the present invention, any
one of first, second, and third rounded tips of the first, second, and
third stylus tips 52, 42, and 72 in FIGS. 2 and 3 may have a hollow
cavity formed therein and a cavity wall thickness. In an embodiment, the
cavity wall may have a thickness ranging from 0.1 to 2 mm. In another
embodiment, the cavity wall may have a thickness ranging from 0.3 to 0.8
mm. In yet another embodiment, the cavity wall may have a thickness
ranging from 0.4 to 0.7 mm. Other embodiments are possible where any one
of first, second, and third rounded tips of the first, second, and third
stylus tips 52, 42, and 72 have their entire volume filled with a filler
material. In an embodiment, the filler material may be the same material
as the stylus tip material. In another embodiment, the filler material
may be a different material from the stylus tip material. Other
embodiments are possible where any one of first, second, and third
rounded tips of the first, second, and third stylus tips 52, 42, and 72
has a spring member inside hollow cavity to optimize the elasticity of
the tips.

[0032] In an embodiment, the tip material comprises a conductive
rubber-based material. In another embodiment, the tip material comprises
a conductive silicone-based material. In yet another embodiment, the tip
material comprises a conductive polymeric fiber-based material.

[0033] In some embodiments the conductivity of any one of first, second,
and third stylus tips 52, 42, and 72 may be improved by having a
conductive coating thereon to render a conductive surface. The conductive
coating may comprise a Ni or Cu coating. In an embodiment, the conductive
coating may comprise a Ni coating having a thickness in the range of
about 0.5 to 2 microns. In another embodiment, the conductive coating may
comprise a Cu coating having a thickness in the range of 5 to 10 microns.

[0034] In one embodiment, the resistivity of any one of first, second, and
third stylus tips 52, 42, and 72 may be between 0.01 and 0.1 Ohms. In
another embodiment, the resistivity may be between 0.1 to 1 Ohms. In yet
another embodiment, the resistivity may be between 1 to 5 Ohms.

[0035] Reliability against repeated use is another design consideration.
In this connection, in an embodiment, any one of first, second, and third
stylus tips 52, 42, and 72 may be designed to withstand 10,000 cycles of
lateral strokes 3 cm in length traversed in 2 seconds in a direction
parallel to a touch screen surface while applying a vertical force of 1.0
N in a direction perpendicular to the touch surface. In another
embodiment, the stylus tip may be designed to withstand 15,000 cycles of
lateral strokes 3 cm in length traversed in 2 seconds in a direction
parallel to a touch screen surface while applying a vertical force of 1.0
N in a direction perpendicular to the touch surface.

[0036] Another aspect of a user experience is the availability of various
tip sizes and their positions within the multi-tip stylus pen 10. For
example, a user may find it convenient to have two most-frequently used
tip sizes disposed at the first body end of the body member 20 and the
second cap end of the hollow cap member 30 such that they are readily
available without having to disengage the hollow cap member 30 from the
body member 20. In addition, a user may find it beneficial to have the
most fragile tip among the multiple tips be disposed at the second body
end of the body member 20 so that it benefits from the protection of the
hollow cap member 30.

[0037] In this connection, in one embodiment of the present invention, the
first rounded tip of the first stylus tip 52 has a first base width
greater than a second base width of the second rounded tip of the second
stylus tip 42. In another embodiment, the second rounded tip of the
second stylus tip 42 has a second base width greater than a third base
width of the third rounded tip of the third stylus tip 72. Various other
embodiments are possible wherein the second base width is greater than
the first base width, third base width is greater than the first base
width, or the third base width is greater than the second base width.

[0038] Referring to FIG. 3, the body member 20 comprises an elongated grip
portion disposed between the second and third stylus tip members 40 and
70. In an embodiment, the grip portion of the body member 20 includes an
elongated cylindrical tube. The grip member may further include a hollow
cavity extending in the lengthwise direction of the cylindrical tube. In
an embodiment where grip member includes a hollow cavity, the cylindrical
tube may have a tube wall having a thickness ranging from 0.1 to 0.5 mm.
In another embodiment, the cylindrical tube may have a tube wall having a
thickness ranging from 0.5 to 1 mm. In yet another embodiment, the
cylindrical tube may have a tube wall having a thickness ranging from 1
to 2 mm.

[0039] While the stylus pen 10 of FIG. 3 shows a body member being a
cylindrical shape, other embodiments are possible. For example, the
geometric shape of the body member may be chosen such that it has at
least one cross sectional area having a shape chosen from the group
consisting of a circle, an oval, a triangle, rectangle, a pentagon, a
hexagon, an octagon, and a diamond. A non-circular symmetric shape may
prevent the multi-tip stylus pen 10 from inadvertently rolling off a
sloped surface, for example a desk.

[0040] The grip portion of the body member 20 may comprise any suitable
material having the weight, stiffness, and other mechanical properties to
enhance the user experience both aesthetically and functionally. A
suitable material for the grip portion of the body member may include a
metal such as brass, stainless steel, aluminum, and titanium. A suitable
material may also include non-metals such as glass, gem, plastic,
ceramic, graphite-reinforced composite materials, and wood-derived
materials.

[0041] One of the considerations in designing the body member 20 is
improving the surface finish to minimize slipping in user's hand,
especially in the presence of moisture. In this connection, in an
embodiment of the present invention, the surface of the body member may
include an anti-slip surface produced at least in part by sanding. In
another embodiment, the surface may include an anodized surface. In these
embodiments, the degree of sanding and anodization is chosen to achieve a
degree of surface roughness in the grip portion of the body member 20
suitable for gripping without slipping in user's hand.

[0042] In the foregoing description of embodiments in connection with
FIGS. 2 and 3, first and second ends of the body member 20 and the second
end of the hollow cap member 30 comprise stylus tip members. Other
embodiments are possible. For example, any one of the first and second
ends of the body member 20 and the second end of the hollow cap member
may comprise a writing member or a light source member.

[0043] In particular, in the embodiment illustrated in FIG. 6, a multi-tip
stylus pen 100 includes an elongated body member 80 having a first end
and a second end and a hollow cap member 30. The hollow cap member
comprises an inner cavity with an opening 32 at a first end configured to
receive the second end of the body member 20. A first stylus tip member
50 comprising a first stylus tip 52 is disposed at the second end of the
hollow cap member 30. The first stylus tip 52 comprises a first rounded
tip of a material and shape suitable for contact with the touchscreen.
The embodiment further comprises a second stylus tip member 40 disposed
at the first end of the body member 80. The second stylus tip member 40
comprises a second stylus tip 42 comprising a second rounded tip of a
material and shape suitable for contact with the touchscreen.

[0044] In the illustrated embodiment in FIG. 6, instead of the third
stylus member 70 of FIGS. 2 and 3, the multi-tip stylus pen 100 comprises
a writing member 90 disposed at a second end of the body member 80. The
writing member comprises a writing tip 92 suitable for writing on a
writing surface. A suitable writing tip 92 includes a ball point tip, a
felt tip, a pencil tip, a marker tip, and the like.

[0045] In the embodiment in FIG. 3, the first, second, and third stylus
tip members 50, 40, and 70 further comprises first, second, and third
link members 54, 44, and 74 that couple the first stylus tip 52 with the
hollow cavity member 30 at the second cap end, the second stylus tip 42
with the body member 20 at its first body end, and the third stylus tip
72 with the body member 20 at its second end. Any one of the first,
second and third link members 54, 44, and 74 may be a double-sided male
connection with a middle stopper. For example, the first link member 54
may have a first male connection inserted into the first stylus tip 52
and a second male connection be inserted into the second end of the
hollow cap member 30. The second link member 44 may have a first male
connection inserted into the second stylus tip 42 and a second male
connection be inserted into the second end of the body member 20.
Similarly, the third link member 74 may have a first male connection
inserted into the third stylus tip 72 and a second male connection be
inserted into the first end of the body member 20. In each of first,
second, and third link members, the middle stopper prevents one of the
male connections from being over-inserted. In addition, each of the
first, second, and third link members may comprise an electrically
conductive material.

[0046] While the first, second, and third link members 54, 44, and 74 are
described as double-sided male connectors, in other embodiments the link
members may have either or both of the male connectors replaced with a
female connector configured to receive a male connector from any one of
the first, second, and third tip members or any one of the first end of
the body member 20, the second end of the body member 20, and the second
cap end of the hollow cap member 30.

[0047] In an embodiment, any one of the first, second, and third link
members 54, 44, and 74 may be a removable link member configured such
that when one or more of the first, second, and third stylus tips 52, 42,
and 72 become worn out, any one of them may be replaced with a
replacement stylus tip by disengaging the stylus tips from the
corresponding removable link.

[0048] The first, second, and third link members 54, 44, and 74 may
comprise a metallic material such as brass, stainless steel, aluminum,
and titanium. In an embodiment, the metallic material may be a C3604-type
brass. In another embodiment, the first, second and third link members
54, 44, and 74 may be chrome-plated.

[0049] In the illustrated embodiment of FIGS. 2 and 3, the hollow cap
member 30 includes an elastic clip 60 designed to attach the hollow cap
member 30 of the multi-tip stylus pen 10 to any sufficiently thin sheets,
such as the cover of the touch screen device 2. The elastic clip 60 is
also designed to attach to clothing, such as a shirt pocket. The elastic
clip 60 is immovably attached to the hollow cap member 30 at a first end
and has a clip head portion 62 at a second end. An elongated lever
portion extends from a point of attachment to the hollow cap member 30
along the axis of the length of the hollow cap member 60 and terminates
at a second end at the clip head portion 62. The elastic clip 60 works
though a lever action such that when the clip head portion 62 is pulled
in a direction perpendicular to the surface of the hollow cap member 30
at a position of overlap between the surface the hollow cap member 30 and
the clip head portion 62, the lever action creates a spring force tending
to pull the head portion 62 back towards the surface of the hollow cap
member 30. The elasticity of the elongated lever portion is designed such
that the hollow cap member 30 and the multi-tip stylus pen 10 may be
attached to a sheet or a shirt pocket without making a permanent mark
thereon. In an embodiment, the elastic clip 60 is designed to withstand a
pulling force of 5.5 lbf to 8.7 lbf measured at the clip head portion
with the force applied for a time exceeding 10 seconds in a direction
perpendicular to the surface of the hollow cap member 30 at the point of
overlap between the surface of the hollow cap member 30 and the clip head
portion 62. In another embodiment, the elastic clip 60 is designed to
withstand a force of 8.7 lbf to 9.6 lbf. In yet another embodiment, the
elastic clip 60 is designed to withstand a force of 9.6 to 20.1 lbf. When
a multi-tip stylus pen having a cylindrical body member 20 and a
cylindrical hollow cap member 30 is placed on a sloped surface, the
elastic clip 60 also prevents the stylus pen 10 from rolling down the
slope to prevent loss or breakage.

[0050] FIG. 4A illustrates an enlarged view of the first stylus tip member
50 disposed at the second cap end the hollow cap member 30. FIG. 4B is an
end view of the enlarged tip member 50 of FIG. 4A, viewed from the second
cap end of the cap member 30 in a direction parallel to an axis of
elongation of the cap member 30 towards the first cap end of the cap
member 30. The views in FIGS. 4A and 4B are enlarged views of the cap
member 30 of FIGS. 2 and 3, annotated with various dimensions according
to an aspect of the present invention. The first stylus tip 52 has a
first base width d1 and a first vertical height h3. In
particular, the first stylus tip 52 in FIGS. 4A and 4B comprises a first
hemispherical dome tip portion and a first cylindrical portion.
Therefore, the first vertical height h3 includes the first
cylindrical portion height h1, and the first base width d1
corresponds to the common diameter of the first hemispherical dome tip
portion and the first cylindrical portion.

[0051] In the illustrated embodiment, the first base width d1 of the
first stylus tip 52 is narrower than the cap width d3 of the cap
member 30. In other embodiments, the first base width d1 may be
equal or wider than the cap width d3 of the cap member 30.

[0052] In an embodiment, the first stylus tip 52 may have a first base
width d1 between 6.5 mm and 9 mm. In another embodiment, the first
stylus tip 52 may have a first base width d1 between 6.5 and 7.5 mm.
In yet another embodiment, the first stylus tip 52 may have a first base
width d1 between 6.7 and 7.3 mm, or about 7.0 mm.

[0053] In an embodiment, the first height h3 is between 3 and 5 mm.
In another embodiment, the first vertical height h3 is between 5 and
7 mm. In yet another embodiment, the first vertical height h3 is
between 7 and 9 mm.

[0054] FIG. 5A illustrates an enlarged view of the second stylus tip
member 40 disposed at the first body end of the body member 20. FIG. 5B
is an end view of the enlarged first tip member 40 of FIG. 4A, viewed
from the first body end of the cap member 30 in a direction parallel to
an axis of elongation of the body member 20 towards the second end of the
body member 20. The views in FIGS. 5A and 5B are enlarged views of the
body member 20 of FIGS. 2 and 3 annotated with various dimensions
according to an aspect of the present invention. The second stylus tip 42
has a second base width d2 and a second vertical height h4. In
particular, the second stylus tip 42 in FIGS. 4A and 4B comprises a
second hemispherical dome tip portion and a second cylindrical portion.
Therefore, the second vertical height h4 includes the second
cylindrical portion height h2 and the second base width d2
corresponds to the common diameter of the second hemispherical dome tip
portion and the second cylindrical portion.

[0055] In the illustrated embodiment, the second base width d2 of the
second stylus tip 42 is narrower than a body width d4 of the body
member 20. In other embodiments, the second base width d2 may be
equal or wider than the body width d4 of the body member 20.

[0056] In an embodiment, the second stylus tip 42 may have a second base
width d2 between 5.5 mm and 6.5 mm. In another embodiment, the
second stylus tip 42 may have a second base width d2 between 5.7 and
6.3 mm. In yet another embodiment, the second stylus tip 42 may have a
second base width d2 between 5.9 and 6.1 mm, or about 6.0 mm.

[0057] In an embodiment, the second height h3 is between 3 and 5 mm.
In another embodiment, the second height h3 is between 5 and 7 mm.
In yet another embodiment, the second height h3 is between 7 and 9
mm.

[0058] While not illustrated the third stylus tip 72 may be configured
similar to the first and second stylus tips 52 and 42. In particular, in
an embodiment, the third stylus tip 72 may have a third base width
d5 and a third vertical height h6. In particular, the third
stylus tip 72 may comprise a third hemispherical dome tip portion and a
third cylindrical portion. Therefore, the third vertical height h6
includes a third cylindrical portion height h5 and the third base
width d5 corresponding to the common diameter of the third
hemispherical dome tip portion and the third cylindrical portion.

[0059] In an embodiment, the third base width d5 of the third stylus
tip 72 may be narrower than a body width d4 of the body member 20.
In other embodiments, the third base width d5 may be equal or wider
than the body width d4 of the body member 20.

[0060] In an embodiment, the third stylus tip 72 may have a third base
width d5 between 1.0 mm and 5.5 mm. In another embodiment, the third
stylus tip 42 may have a third base width d5 between 3 mm and 5.3
mm. In yet another embodiment, the third stylus tip 72 may have a third
base width d3 between 4.8 and 5.2 mm, or about 5.0 mm.

[0061] In an embodiment, the third height h6 is between 3 and 5 mm.
In another embodiment, the third height h6 is between 5 and 7 mm. In
yet another embodiment, the third height h6 is between 7 and 9 mm.

[0062] Although this invention has been described in terms of certain
embodiments, other embodiments that are apparent to those of ordinary
skill in the art, including embodiments that do not provide all of the
features and advantages set forth herein, are also within the scope of
this invention. Moreover, the various embodiments described above can be
combined to provide further embodiments. In addition, certain features
shown in the context of one embodiment can be incorporated into other
embodiments as well. Accordingly, the scope of the present invention is
defined only by reference to the appended claims.